From the article:

> If config?.Settings is null, the assignment is skipped.

If the right hand expression has side effects, are they run? I guess they do, and that would make the code more predictable.

▲ Izikiel43 5 days ago | parent | next [-]

From the article as well:

Side-Effect Prevention When a null-conditional statement assignment is evaluated, the right-hand side of the expression is not executed unless the left-hand side is defined.

▲ gus_massa 5 days ago | parent [-]

Thanks. I missed it.

I really dislike that, because it hides the control flow too much. Perhaps I'm biased by Racket, where it's easy to define something weird using macros, but you should not do unexpected weird things.

For example you can define vector-set/drop that writes a value to a position of a vector, but ignores the operation when the position is outside the vector. For example

  (vector-set/drop v -2 (print "banana"))

With a macro is possible to skip (print "banana") because -2 is clearly out of range, but if you do that everyone will hate you.

▲

ygra 5 days ago | parent [-]

I think in the context of C# this is not exactly unexpected since there are various operators that apply conditional execution (and evaluation) to parts of an expression. All of them start with ?, though (? :, ??, ?., ?[], ??=), so except for casts to nullable types, every question mark in an expression signals that control flow is about to happen and it's been that way in C# for quite a while.

	▲	gus_massa a day ago \| parent [-]
		[Too late, sorry for the delay, but I had to think about it.] That ooks like a good reason. Looking at https://learn.microsoft.com/en-us/dotnet/csharp/language-ref... , the magic is in the LHS or the RHS, and in ??= the magic is explicitly in the connection. Here, IMHO, the problem is that the magic jumps from one side to the other. Anyway, I don't use C#.

▲ 5 days ago | parent | prev [-]

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